The present invention relates to a revolving drill head or the like with finely adjustable tool carriers at right angles to its longitudinal axis having high rigidity material-elastic intermediate members operable by a hydraulic pressure medium supplied coaxially to the shaft of the drill head in a feed mechanism, which is positioned in fixed manner between the shaft and the tool carrier and having two flange-like connecting parts to the shaft or tool carrier connected by two axially parallel, resilient parts at right angles to the shaft axis as a parallel guide and with counter-directed, diametrically facing shaft axis parallel extensions which are symmetrical to and spaced from the shaft axis and between which is provided an expansion member as a material-elastic intermediate member in a plane at right angles to the shaft axis, each of the flange-like connecting parts has a compensating device diametrically facing with respect to the shaft axis the extension fixed thereto for compensating its unbalance in at least one relative position of the one flange-like connecting part with respect to the other flange-like connecting part and the flange-like connecting parts are jointly surrounded by a cylindrical sleeve.
In the case of the drill head of the aforementioned type described in German Pat. No. 20 34 601 for reducing or eliminating the unbalance of the arrangement occurring through the tool carrier or the forces exerted by it on the drilling spindle and on the feed mechanism the extensions fixed to the flange parts have diametrically facing, special balance weights, which ensure that the centre of gravity of the arrangement is in the shaft axis or rotation axis of the drill head in at least one position of the feed mechanism. The cylindrical sleeve surrounding the two flange-like connecting parts is used for protecting the inner parts against contamination.
The known drill head with the construction of the unbalance compensating means provided therein has proved satisfactory in principle. However, it has proved desirable to further simplify the construction of the feed mechanism by reducing the number of components necessary.
The problem of the present invention is to improve the aforementioned drill head so that on further simplifying the construction, it is possible to cut down on manufacturing costs and also the weight, whilst further increasing the operating reliability due to the simpler construction.